title: A novel de novo mutation within EFNB1 gene in a young girl with craniofrontonasal syndrome.
abstract: Craniofrontonasal syndrome is mainly characterized by frontonasal dysplasia, telorbitism, a broad nasal root, and frequently a bifid nose and coronal craniosynostosis. Craniofrontonasal syndrome is an X-linked disorder with an unusual pattern of inheritance because heterozygous females are more severely affected than hemizygous males. The craniofrontonasal syndrome-causing gene is EFNB1, localized in the border region of chromosome Xq12 and Xq13.1, encoding for protein ephrin-B1. Here we aim to investigate the underlying genetic defect of a young girl with craniofrontonasal syndrome. The patient underwent surgical correction of her craniofacial deformities. Genetic analysis was carried out by polymerase chain reaction. Products of exon 2 of the EFNB1 gene were sequenced as well as digested with BpmI enzyme. A novel de novo missense mutation 373G>A was identified within the EFNB1 gene, leading to the replacement of glutamic acid at amino acid position 125 with lysine. The replacement of Glu125 with Lys, which lies within the G-H loop, part of the dimerization ligand-receptor interface, is expected to disrupt the interaction between the Eph receptor and ephrin B1 ligand, thus leading to craniofrontonasal syndrome.
authors.affiliation: Department of Genetics and Biotechnology, Faculty of Biology, School of Physical Sciences, National and Kapodistrian University of Athens, Panepistimioupolis, GR-157 01, Athens, Greece. bio762@edu.biology.uoc.gr
authors.forename: Despina
authors.initials: D
authors.lastname: Apostolopoulou
authors.forename: Alexander
authors.initials: A
authors.lastname: Stratoudakis
authors.forename: Angeliki
authors.initials: A
authors.lastname: Hatzaki
authors.forename: Olga S
authors.initials: OS
authors.lastname: Kaxira
authors.forename: Kanaris P
authors.initials: KP
authors.lastname: Panagopoulos
authors.forename: Panagoula
authors.initials: P
authors.lastname: Kollia
authors.forename: Vassiliki
authors.initials: V
authors.lastname: Aleporou
mesh_terms: D000293:Adolescent; D019465:Craniofacial Abnormalities / Q000000981:diagnostic imaging / Q000235:genetics* / Q000601:surgery; D036387:Ephrin-B1 / Q000235:genetics*; D005091:Exons; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D009154:Mutation; D017422:Sequence Analysis, DNA; D013577:Syndrome; D014057:Tomography, X-Ray Computed
chemical_list: C484288:EFNB1 protein, human; D036387:Ephrin-B1